Preparation process of medical comfortable cotton-like fabric

Abstract

The application relates to a preparation process of a medical comfortable cotton-imitating fabric, and belongs to the technical field of textile processing, which comprises the following steps: fiber surface micro-etching and activation: a polyester base cloth is immersed into an alkali-reducing working solution containing sodium hydroxide and a quaternary ammonium salt type accelerator, and is subjected to immersion treatment at 95-100 DEG C for 30-50 min; after being taken out, the base cloth is washed to be neutral and dried, so that pretreated fabric with a micro-pit structure and exposed end hydroxyl and end carboxyl groups is obtained; the concentration of sodium hydroxide in the alkali-reducing working solution is 15-25 g / L, and the concentration of the accelerator is 0.5-1.0 g / L; the application not only reduces the bending stiffness of the fiber in a physical aspect, so that the fiber is closer to the low modulus characteristic of natural cotton, but also provides a large number of physical anchoring sites for subsequent finishing agents.

Description

Technical Field

[0001] This invention relates to the field of textile processing, specifically to a process for preparing a medical-grade comfortable cotton-like fabric. Background Technology

[0002] In the medical and health field, polyester fabrics are widely used in surgical gowns, bedding and various medical protective textiles due to their excellent physical strength and chemical stability; however, due to the high crystallinity and smooth cylindrical structure of polyester fibers, these fabrics exhibit significant defects in practical applications. Existing medical polyester fabrics generally have poor moisture absorption and wicking properties, making it difficult for moisture to diffuse and penetrate on the fiber surface. This can cause a stuffy feeling when medical staff or patients wear them for a long time. Although conventional chemical finishing methods can temporarily improve the feel of the fabric, the finishing agents are easily lost in the high-frequency medical chlorine disinfection and washing environment, causing the fabric to quickly return to a dry, hard, and rough state and lose its original protective function. In addition, traditional finishing processes often lead to fiber adhesion while improving functionality, which increases the fabric’s bending stiffness, makes it feel stiff, and lacks the fluffiness and softness of natural cotton fibers. Existing technologies cannot achieve efficient moisture wicking, long-lasting antibacterial ability, and a cotton-like comfortable feel while ensuring the fabric’s breaking strength. The information disclosed in the background section above is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0003] The purpose of this invention is to provide a process for preparing medical-grade comfortable cotton-like fabric to solve the problems mentioned in the background art.

[0004] The technical solution of the present invention includes the following steps: (1) Fiber surface micro-etching and activation: The polyester base fabric is immersed in an alkali reduction working solution containing sodium hydroxide and quaternary ammonium salt accelerator, and treated at 95-100℃ for 30-50 min. After removal, it is washed with water until neutral and dried to obtain a pretreated fabric with a micro-pit structure on the surface and exposed terminal hydroxyl and terminal carboxyl groups. The concentration of sodium hydroxide in the alkali reduction working solution is 15-25 g / L, and the concentration of accelerator is 0.5-1.0 g / L. (2) Synthesis of reactive ternary copolymer modifier: Hydrogen-containing silicone oil and isopropanol dried by molecular sieve are mixed at a mass ratio of 1:0.8 to 1:1.2 and added to a reactor equipped with a reflux condenser. The temperature is raised to 75-85°C, and chloroplatinic acid catalyst at 10-20 ppm relative to the total mass of the reactants is added. A mixed monomer solution is added dropwise at a stirring speed of 200-500 rpm. The mixed monomer solution consists of allyl polyoxyethylene ether, methacryloyloxyethyltrimethylammonium chloride, and 3 The modified polysiloxane emulsion is composed of (2,3-epoxypropoxy)propyltrimethoxysilane and contains hydrogen silicone oil, allyl polyoxyethylene ether, methacryloyloxyethyltrimethylammonium chloride, and 3-(2,3-epoxypropoxy)propyltrimethoxysilane in a mass ratio of 100:25~35:8~12:4~6. After the addition is complete, the mixture is refluxed at 75~85℃ for 4~6 hours. After the reaction is completed, the solvent is removed by vacuum distillation, and water is added for phase inversion chemical emulsification to obtain a modified polysiloxane emulsion with a solid content of 30%. (3) Crosslinking-enhanced padding finishing: Prepare a finishing working solution, which includes 30-50 g / L of the modified polysiloxane emulsion prepared in step (2), 10-15 g / L of the blocked polyisocyanate crosslinking agent with methyl ethyl ketone oxime or ε-caprolactam as the blocking agent, 1-2 g / L of nonionic penetrant, and adjust the pH value to 5.5-6.5 with glacial acetic acid; immerse the pretreated fabric obtained in step (1) into the finishing working solution for two dips and two pads, and control the padding rate to 70%-80%; (4) Gradient thermal crosslinking curing: The fabric treated in step (3) is pre-baked at 100-110℃ for 120-150s, and then heated to 170-180℃ for baking for 50-80s, so that the blocked isocyanate is unblocked and the modified polysiloxane is covalently bonded to the fiber surface active groups to form a network crosslinking film. (5) Airflow mechanical softening: The fabric cured in step (4) is sent into an airflow softener. Driven by a high-speed hot airflow at 120°C and a nozzle pressure of 0.3-0.5MPa, the fabric undergoes high-frequency collision and rubbing in the Venturi tube. The processing time is 20-40 minutes, and a medical-grade comfortable imitation cotton fabric is obtained.

[0005] Preferably, the accelerator in step (1) is hexadecyltrimethylammonium bromide.

[0006] Preferably, the hydrogen content of the hydrogen-containing silicone oil in step (2) is 0.18% to 0.3%; and the amount of the chloroplatinic acid catalyst is 10 to 20 ppm of the total mass of the reaction system.

[0007] Preferably, the mass ratio of the hydrogen-containing silicone oil, allyl polyoxyethylene ether, methacryloyloxyethyl trimethylammonium chloride, and 3-(2,3-epoxypropoxy)propyltrimethoxysilane in step (2) is 100:25-35:8-12:4-6.

[0008] Preferably, the molecular weight of the allyl polyoxyethylene ether in step (2) is 400 to 600.

[0009] Preferably, the unblocking temperature of the blocked polyisocyanate crosslinking agent using methyl ethyl ketone oxime or ε-caprolactam as the blocking agent in step (3) is 130°C.

[0010] A medical-grade comfortable cotton-like fabric, wherein irregular micro-pits are distributed on the fiber surface of the fabric, and the micro-pits and the fiber surface are anchored by chemical cross-linking of a terpolymer cross-linking network containing polyether segments, quaternary ammonium salt groups and epoxy groups.

[0011] This invention provides an improved process for preparing a medical-grade comfortable cotton-like fabric, which, compared with existing technologies, has the following improvements and advantages: 1. This solution uses a specific alkali reduction process to stabilize the polyester fiber reduction rate between 10% and 15%. This process removes the amorphous regions on the fiber surface. For example, under the condition of a reduction rate of 10% to 15%, an irregular micro-pit structure with an average pore size of about 0.8 μm can be formed. This structure not only reduces the bending stiffness of the fiber at the physical level, making it closer to the low modulus characteristics of natural cotton, but also provides a large number of physical anchoring sites for subsequent finishing agents. 2. The modified polysiloxane emulsion synthesized in this invention contains epoxy groups and methoxysilane groups, combined with a blocked polyisocyanate crosslinking agent using methyl ethyl ketone oxime or ε-caprolactam as a blocking agent. During the gradient curing process, it covalently bonds with the terminal hydroxyl and terminal carboxyl groups on the fiber surface. Test data shows that after 50 medical chlorine-containing disinfection washes, the fabric can still maintain an antibacterial rate of over 98% against Staphylococcus aureus and Escherichia coli. In contrast, the antibacterial rate of the control group lacking anchoring groups or crosslinking agents decreased significantly, proving the robustness of the three-dimensional interpenetrating network structure of this solution. 3. Through airflow mechanical softening, under the combined action of high-temperature hot airflow at 120℃ and mechanical kneading with a Venturi tube, the fiber adhesion that may be caused by chemical cross-linking is effectively eliminated. Bending stiffness test shows that the stiffness of the finished fabric is significantly lower than that of untreated or chemically treated samples. At the same time, due to the introduction of polyether segments in the modifier and the capillary effect of the micro-pit structure, the water droplet diffusion time is greatly shortened, giving the fabric excellent moisture absorption and perspiration wicking properties. Detailed Implementation

[0012] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments. Example 1:

[0013] This invention provides a process for preparing a medical-grade comfortable cotton-like fabric, comprising the following steps: (1) Micro-etching and activation of fiber surface: The polyester base fabric is immersed in an alkaline weight reduction working solution containing sodium hydroxide and quaternary ammonium salt accelerator, and treated at 95-100°C for 30-50 minutes. After removal, it is washed with water until neutral and dried to obtain a pretreated fabric with a micro-pit structure on the surface and exposed terminal hydroxyl and terminal carboxyl groups; the concentration of sodium hydroxide in the alkaline weight reduction working solution is 15-25 g / L, and the concentration of the accelerator is 0.5-1.0 g / L; the accelerator is hexadecyltrimethylammonium bromide; the weight reduction rate of the polyester base fabric after treatment is controlled at 10%-15%; This embodiment is the best implementation method, specifically using mild etching conditions of 95°C and 15 g / L sodium hydroxide, combined with 0.5 g / L hexadecyltrimethylammonium bromide (CTAB) as a cationic promoter, and the treatment time is set to 30 min to stabilize the weight reduction rate at 10%. In this step, CTAB accelerates the penetration of sodium hydroxide into the amorphous region of the fiber by reducing the solid-liquid interfacial tension, triggering a nucleophilic substitution hydrolysis reaction of ester bonds in the polyester molecular chain. This specific combination of parameters is designed to perform controlled peeling on the fiber surface, forming irregular micro-pits with an average pore size of about 0.8 μm, while exposing a high density of terminal hydroxyl and terminal carboxyl groups in situ. These active sites are key anchoring points for subsequent chemical grafting, and the 10% reduction rate maximizes the preservation of the tensile strength of the base fabric, avoiding fabric brittleness caused by excessive etching. (2) Synthesis of reactive ternary copolymer modifier: Hydrogen-containing silicone oil and isopropanol dried by molecular sieve were mixed at a mass ratio of 1:0.8 to 1:1.2 and added to a reactor equipped with a reflux condenser. The temperature was raised to 75-85°C, and chloroplatinic acid catalyst at 10-20 ppm relative to the total mass of the reactants was added. The mixed monomer solution was added dropwise at a stirring speed of 200-500 rpm. The mixed monomer solution consisted of allyl polyoxyethylene ether, methacryloyloxyethyltrimethylammonium chloride, 3- The mixture is composed of (2,3-epoxypropoxy)propyltrimethoxysilane, and contains hydrogen silicone oil, allyl polyoxyethylene ether, methacryloyloxyethyltrimethylammonium chloride, and 3-(2,3-epoxypropoxy)propyltrimethoxysilane in a mass ratio of 100:25-35:8-12:4-6. After the addition is complete, the mixture is refluxed at 75-85℃ for 4-6 hours. After the reaction is completed, the solvent is removed by vacuum distillation, and water is added for phase inversion chemical emulsification to obtain a modified polysiloxane emulsion with a solid content of 30%. The specific emulsification process is as follows: 5%-8% of fatty alcohol polyoxyethylene ether by mass of the product is added to the product after vacuum distillation. Deionized water is slowly added dropwise while stirring at 1000-1500 rpm until the system undergoes a phase inversion from water-in-oil to oil-in-water. Water is then added to dilute the mixture until the solid content is 30%. The hydrogen content of the hydrogen-containing silicone oil is 0.18%-0.3%, and the molecular weight of the allyl polyoxyethylene ether is 400-600. In this embodiment, hydrogen-containing silicone oil with a hydrogen content of 0.18% is mixed with isopropanol at a ratio of 1:0.8. The monomer is added dropwise at a mass ratio of 100:25:8:4 under the catalysis of 10ppm chloroplatinic acid at 75°C. Short-chain allyl polyoxyethylene ether with a molecular weight of 400 is selected and the mixture is refluxed for 4 hours. In this synthetic system, isopropanol, as a solvent, effectively suppressed the dramatic increase in system viscosity, ensuring the mass transfer efficiency of the hydrosilylation reaction. Short-chain polyethers and a low proportion of hydrophilic monomers were selected to construct a compact and highly permeable modified layer structure. The epoxy and methoxysilyl groups in the terpolymer provide dual chemical anchoring capabilities, while the quaternary ammonium salt groups endow the polymer with inherent broad-spectrum antibacterial properties. This molecular design solves the problem of traditional silicone oil finishing being not washable through covalent bonding. (3) Crosslinking-enhanced padding finishing: Prepare a finishing working solution containing 30-50 g / L of the modified polysiloxane emulsion prepared in step (2), 10-15 g / L of the blocked polyisocyanate crosslinking agent with methyl ethyl ketone oxime or ε-caprolactam as the blocking agent, and 1-2 g / L of nonionic penetrant, and adjust the pH value to 5.5-6.5 with glacial acetic acid; immerse the pretreated fabric obtained in step (1) into the finishing working solution for two dips and two pads, and control the padding rate to 70%-80%; the unblocking temperature of the blocked polyisocyanate crosslinking agent with methyl ethyl ketone oxime or ε-caprolactam as the blocking agent is 130℃; The finishing solution configured in this embodiment contains 30 g / L modified emulsion, 10 g / L crosslinking agent, and 1 g / L penetrant, with the pH adjusted to 5.5 and the pick-up rate controlled at 70%. In this acidic microenvironment, the quaternary ammonium salt groups in the modifier maintain positive charge and electrostatically adsorb onto the negatively charged polyester fiber surface after micro-etching, through carboxyl ionization, achieving directional alignment of the finishing agent on the fiber surface. The blocked isocyanate acts as a chemical bridge, remaining in a latent state to prevent premature crosslinking reactions in the working solution and ensuring the stability of the finishing solution during its service life. (4) Gradient thermal crosslinking curing: The fabric treated in step (3) is pre-baked at 100-110℃ for 120-150s, and then heated to 170-180℃ for baking for 50-80s, so that the blocked isocyanate is unblocked and the modified polysiloxane is covalently bonded to the fiber surface active groups to form a network crosslinking film. This embodiment employs a gradient curing process involving pre-drying at 100℃ for 120 seconds and baking at 170℃ for 50 seconds. The pre-drying stage aims to remove moisture and allow the emulsion particles to break down and spread. The baking stage, at a temperature higher than the unsealing temperature of the crosslinking agent (130℃), promotes the release of isocyanate groups (-NCO). These highly active groups then undergo a cascade reaction with hydroxyl groups on the fiber surface, hydroxyl groups in the modifier, and epoxy ring-opening products to generate urethane bonds and urea bonds. This in-situ constructed interpenetrating network structure firmly locks the modified polymer within the micro-pits on the fiber surface, significantly improving wash resistance. (5) Airflow mechanical softening: The fabric cured in step (4) is sent into an airflow softener. Driven by a high-speed hot airflow at 120°C and a nozzle pressure of 0.3-0.5MPa, the fabric undergoes high-frequency collision and rubbing in the Venturi tube. The processing time is 20-40 minutes, and a medical comfortable imitation cotton fabric is obtained. In this embodiment, the processing time is set to 20 minutes. Regarding the temperature setting, research has shown that 120℃ is the optimal critical point for balancing fabric bulkiness and physical strength. Although the effective process window can cover 115℃ to 125℃, 120℃ is the most suitable. At this temperature, the modified polysiloxane crosslinked film is in a highly elastic state. The turbulence effect generated by the high-speed hot airflow can efficiently break up the slight adhesion between fibers caused by chemical crosslinking. This avoids the film becoming hard and difficult to break apart due to excessively low temperatures (below 110℃) or excessively high temperatures (above 130℃) causing the finishing agent to yellow or the fibers to shrink due to excessive heat. Meanwhile, the mechanical kneading action inside the Venturi tube reduces the bending stiffness of the fibers, giving the fabric a fluffy and soft feel similar to natural cotton. The resulting fabric has irregular micro-pits distributed on the fiber surface, and the micro-pits and fiber surface are anchored by chemical cross-linking of a terpolymer cross-linking network containing polyether segments, quaternary ammonium salt groups and epoxy groups. This network structure gives the fabric basic hydrophilicity and antibacterial properties. Example 2:

[0014] This embodiment provides a process for preparing a medical-grade comfortable cotton-like fabric. All steps and parameter ranges are based on the above, with the difference being the adjustment of specific process parameters. This embodiment aims to obtain the best dual effects of moisture absorption and antibacterial properties. The specific parameters are adjusted as follows: In step (1), the alkali reduction process is upgraded to 97°C and 20g / L sodium hydroxide, treated for 40min, and the accelerator concentration is 0.75g / L, so that the reduction rate reaches 12.5%. This medium-intensity etching creates deeper and more uniformly distributed micro-pits on the fiber surface, which significantly improves the physical adsorption sites of the subsequent finishing agent. In step (2) of the synthesis, the ratio of hydrogen-containing silicone oil (0.24% hydrogen content) to isopropanol was adjusted to 1:1, the monomer ratio was adjusted to 100:30:10:5, and a polyether with a molecular weight of 500 was selected. This formulation balances the hydrophilic segment length and cationic charge density of the modifier; In step (3), the emulsion concentration in the finishing solution is 40 g / L, the crosslinking agent is 12.5 g / L, the pH is 6.0, and the pick-up rate is 75%. Step (4) Curing conditions: pre-dry at 105℃ for 135s, then bake at 175℃ for 65s. Step (5) Airflow finishing for 30min, with strict temperature control at 120℃. If the temperature fluctuates below 110℃, the fabric feel will not improve significantly and the fluffiness will be insufficient. If the temperature exceeds 130℃, it will damage the stability of the quaternary ammonium salt groups and reduce the antibacterial effect. The constant temperature environment of 120℃ combined with mechanical kneading ensures that the dense interpenetrating network achieves a flexible transformation without brittle breakage. This parameter combination constructs a dense interpenetrating network, which, while ensuring excellent washability, gives the fabric a touch close to natural cotton and rapid moisture wicking ability, making it suitable for medical bedding with balanced functional requirements. Example 3:

[0015] This embodiment provides a process for preparing a medical-grade comfortable cotton-like fabric. All steps and parameter ranges are based on the above, with the difference being the adjustment of specific process parameters. This embodiment uses a combination of parameters at the upper limit of the process range to cope with the high-intensity medical washing environment; in step (1), 25g / L sodium hydroxide, 100℃ high temperature and 1.0g / L accelerator are used for treatment for 50min to achieve a maximum weight reduction rate of 15%; this deep micro-etching greatly changes the original smooth cylindrical shape of polyester fiber and creates a surface roughness that is closest to that of natural cotton fiber. In step (2), silicone oil with a hydrogen content of 0.3% and long-chain polyether with a molecular weight of 600 are selected and functional monomers are introduced in a high ratio of 100:35:12:6, in order to synthesize a copolymer with the highest grafting rate, the longest hydrophilic segment and the highest cationic density. Step (3) The concentration of the finishing solution was increased to 50 g / L, the crosslinking agent was 15 g / L, the pH was 6.5, and the roll-off rate was 80%, thus constructing a thick and highly crosslinked functional film on the fiber surface; Step (4) The fiber was baked at 180℃ for 80 seconds to ensure complete conversion of the reaction sites. Step (5) airflow finishing is extended to 40 minutes. Under constant temperature conditions of 120℃, the heat energy effectively relaxes the internal stress introduced by high-density cross-linking. Experiments show that this temperature setting is particularly critical for highly cross-linked systems. Too low a temperature fails to overcome the rigid constraints of the high-density cross-linking points, resulting in a stiff, matte feel; too high a temperature may lead to thermal degradation of the cross-linked network. Through the coupling of 120°C hot airflow and prolonged mechanical action, the adhesion caused by the high concentration of cross-linking agent is effectively broken up. The fabric prepared in this embodiment exhibits excellent wash resistance and long-lasting antibacterial and hydrophilic properties. Example 4:

[0016] This embodiment provides a process for preparing a medical-grade comfortable cotton-like fabric. All steps and parameter ranges are based on the above, with the difference being the adjustment of specific process parameters. This embodiment selects a relatively mild parameter combination to explore the process effect under low energy consumption; Step (1) The material was treated at 96℃ with 18g / L sodium hydroxide for 35min, and the weight loss rate was controlled at 11%. Step (2) The monomer ratio was 100:28:9:4.5, the polyether molecular weight was 450, and the hydrogen content of the hydrogen-containing silicone oil was 0.20%. Step (3) The finishing solution emulsion concentration was 35g / L, the crosslinking agent was 11g / L, the pH was 5.8, and the pick-up rate was 72%, forming a thin but continuous functional film, which reduced the impact on the breathability of the fabric. Step (4) involves baking at 172℃ for 55 seconds, which balances crosslinking efficiency and production speed; Step (5) involves airflow finishing for 25 minutes. This solution ensures that the fabric has a good cotton-like feel and antibacterial properties while effectively controlling production costs, making it suitable for the high-volume medical textile market that is highly sensitive to costs. Example 5:

[0017] This embodiment provides a process for preparing a medical-grade comfortable cotton-like fabric. All steps and parameter ranges are based on the above, with the difference being the adjustment of specific process parameters. This embodiment uses a high-end parameter configuration, which is particularly suitable for textiles used in intensive care units; Step (1) involves treatment at 99℃ with 22g / L sodium hydroxide for 45min, resulting in a weight reduction rate of 14%, close to the upper limit of the process. Step (2) involves a monomer ratio of 100:32:11:5.5, a polyether molecular weight of 550, and a hydrogen content of 0.28% in the hydrogen-containing silicone oil, which gives the modifier stronger reactivity and higher density of antibacterial groups. Step (3) The emulsion concentration of the finishing solution is 45 g / L, the crosslinking agent is 14 g / L, the pH is 6.2, and the roll-off rate is 78%, to ensure that the functional layer is fully filled in the deep etched micro-pits; Step (4) involves baking at 178℃ for 70 seconds to promote deep cross-linking. Step (5) involves air finishing for 35 minutes. The fabric prepared by this method achieves an excellent balance between durability and comfort. Comparative Example 1:

[0018] This comparative example provides a fabric preparation process, which differs from Example 2 only in that: in step (1), no alkali reduction micro-etching and activation treatment is performed, and the untreated polyester base fabric is directly used for padding in step (3). The remaining steps and parameters are consistent with Example 2. This comparative example aims to verify the influence of the micro-pit structure on the fiber surface and the exposed terminal hydroxyl / carboxyl groups on the anchoring effect of the modifier and the final hand feel of the fabric, and is used to simulate the traditional finishing process without surface modification. Comparative Example 2:

[0019] This comparative example provides a fabric preparation process, which differs from Example 2 only in that: 3-(2,3-epoxypropoxy)propyltrimethoxysilane monomer is not added in step (2), that is, the synthesized modifier is a binary copolymer, which lacks epoxy / silane anchoring groups that can react with crosslinking agents and fibers. The remaining steps and parameters are consistent with Example 2. This comparative example aims to verify the contribution of anchoring groups in reactive ternary copolymer structure to crosslinking network formation and washability. Comparative Example 3:

[0020] This comparative example provides a fabric preparation process, which differs from Example 2 only in that: in step (3), no blocked polyisocyanate crosslinking agent with methyl ethyl ketone oxime or ε-caprolactam as a blocking agent is added, and the remaining steps and parameters are consistent with Example 2; this comparative example aims to verify the key role of external crosslinking agents in constructing a network crosslinked film and improving the durability of finishing agents. Comparative Example 4:

[0021] This comparative example provides a fabric preparation process, which differs from Example 2 only in that: airflow mechanical softening is not performed in step (5), and the fabric after curing in step (4) is the finished product. The remaining steps and parameters are consistent with Example 2. This comparative example aims to verify the necessity of airflow mechanical finishing in breaking the adhesion caused by chemical cross-linking, improving the cotton-like feel and fluffiness of the fabric. Verification experiment:

[0022] To verify the preparation process of the present invention and the performance of the obtained fabric, systematic performance tests were conducted on the fabrics prepared in Examples 1-5 and Comparative Examples 1-4. Testing standards:

[0023] Hand feel evaluation, bending stiffness: According to JISL1096:20108.21.1 Method A, it was measured using a KES-FB2 pure bending tester. The smaller the value, the softer the fabric and the closer it is to cotton feel. Water absorption and water droplet diffusion time: Tested according to AATCC79 standard, record the time from when the water droplet contacts the fabric to when it completely diffuses and disappears. The shorter the time, the better the hydrophilicity. Repeat the test 5 times and take the average value. Wash resistance and antibacterial properties: According to GB / T20944.3 standard, the fabric was tested after 50 medical chlorine disinfection washes with an effective chlorine concentration of 500 mg / L and a temperature of 70°C to determine the antibacterial rate against Staphylococcus aureus and Escherichia coli. Breaking strength retention rate: According to GB / T3923.1 standard, calculate the percentage of warp breaking strength retained by the finished fabric relative to the original fabric. Specific testing process:

[0024] All samples were tested after 24 hours of conditioning under standard atmospheric conditions, with a temperature of 20±2℃ and a relative humidity of 65±4%. For the wash resistance test, an industrial washing machine was used to simulate the standard hospital washing program. Chlorine-containing disinfectant laundry detergent was used as the detergent, and the washing cycle was 50 times. After washing, the samples were air-dried naturally for antibacterial testing.

[0025] Table 1 Performance test data of Examples 1-5 and Comparative Examples 1-4

[0026] As can be seen from the data analysis in Table 1, the medical-grade comfortable cotton-like fabric prepared by this invention exhibits significant advantages in all key indicators. The experiment using ordinary amino silicone oil instead of the modified polysiloxane of this invention highlights the technological advancement of the terpolymer. The mechanism link between micro-etching and hand feel: As the alkali reduction rate increased from 10% in Example 1 to 15% in Example 3, the bending stiffness of the fabric decreased from 0.048 to 0.042 gf·cm² / cm, indicating that the micro-etching technology effectively removed the amorphous regions on the surface of the synthetic fibers, reduced the fiber modulus, and significantly improved the softness; compared with Example 2 and Comparative Example 1, 0.045 vs 0.082, the unetched fabric had a stiff hand feel, confirming the necessity of the micro-pit structure for breaking the plastic feel of polyester fibers; Causal analysis of chemical anchoring and wash resistance: After 50 rigorous medical chlorine-containing washes, the antibacterial rate of the example group remained above 98%; in contrast, the antibacterial rates of Comparative Example 2 (without anchoring groups) and Comparative Example 3 (without crosslinking agents) dropped significantly to 45.8% and 25.6%, respectively. This profoundly reveals the key role of the three-dimensional interpenetrating network of the terpolymer-isocyanate-fiber surface: only through the covalent bonding formed by epoxy groups and isocyanate can functional molecules be firmly locked in the micro-pits on the fiber surface to resist the peeling effect of high-temperature and strong alkaline washing. Physical effects of airflow finishing: Compared with Example 2 and Comparative Example 4, although the chemical formula is the same, Comparative Example 4, which lacks airflow mechanical finishing, has a bending stiffness as high as 0.075 and a poor hand feel; This shows that although chemical crosslinking improves durability, it also causes adhesion between fibers. The adhesion points must be broken by high-speed airflow physical kneading in step (5) in order to finally give the fabric the ideal cotton-like fluffy feel. In summary, this invention successfully solves the problems of poor moisture absorption, easy bacterial growth, and stiff feel of traditional medical polyester fabrics through a synergistic mechanism of chemical micro-etching for hole creation, reactive modifier filling and anchoring, and physical mechanical kneading.

[0027] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A manufacturing process for a medical-grade comfortable cotton-like fabric, characterized in that, Includes the following steps: (1) Fiber surface micro-etching and activation: The polyester base fabric is immersed in an alkali reduction working solution containing sodium hydroxide and quaternary ammonium salt accelerator, and treated at 95-100℃ for 30-50 min. After removal, it is washed with water until neutral and dried to obtain a pretreated fabric with a micro-pit structure on the surface and exposed terminal hydroxyl and terminal carboxyl groups. The concentration of sodium hydroxide in the alkali reduction working solution is 15-25 g / L, and the concentration of accelerator is 0.5-1.0 g / L. (2) Synthesis of reactive ternary copolymer modifier: Hydrogen-containing silicone oil and isopropanol dried by molecular sieve are mixed at a mass ratio of 1:0.8 to 1:1.2 and added to a reactor equipped with a reflux condenser. The temperature is raised to 75-85°C, and chloroplatinic acid catalyst at 10-20 ppm relative to the total mass of the reactants is added. A mixed monomer solution is added dropwise at a stirring speed of 200-500 rpm. The mixed monomer solution consists of allyl polyoxyethylene ether, methacryloyloxyethyltrimethylammonium chloride, and 3 The modified polysiloxane emulsion is composed of (2,3-epoxypropoxy)propyltrimethoxysilane and contains hydrogen silicone oil, allyl polyoxyethylene ether, methacryloyloxyethyltrimethylammonium chloride, and 3-(2,3-epoxypropoxy)propyltrimethoxysilane in a mass ratio of 100:25~35:8~12:4~6. After the addition is complete, the mixture is refluxed at 75~85℃ for 4~6 hours. After the reaction is completed, the solvent is removed by vacuum distillation, and water is added for phase inversion chemical emulsification to obtain a modified polysiloxane emulsion with a solid content of 30%. (3) Crosslinking-enhanced padding finishing: Prepare a finishing working solution, which includes 30-50 g / L of the modified polysiloxane emulsion prepared in step (2), 10-15 g / L of the blocked polyisocyanate crosslinking agent with methyl ethyl ketone oxime or ε-caprolactam as the blocking agent, 1-2 g / L of nonionic penetrant, and adjust the pH value to 5.5-6.5 with glacial acetic acid; immerse the pretreated fabric obtained in step (1) into the finishing working solution for two dips and two pads, and control the padding rate to 70%-80%; (4) Gradient thermal crosslinking curing: The fabric treated in step (3) is pre-baked at 100-110℃ for 120-150s, and then heated to 170-180℃ for baking for 50-80s, so that the blocked isocyanate is unblocked and the modified polysiloxane is covalently bonded to the fiber surface active groups to form a network crosslinking film. (5) Airflow mechanical softening: The fabric cured in step (4) is sent into an airflow softener. Driven by a high-speed hot airflow at 120°C and a nozzle pressure of 0.3-0.5MPa, the fabric undergoes high-frequency collision and rubbing in the Venturi tube. The processing time is 20-40 minutes, and a medical-grade comfortable imitation cotton fabric is obtained.

2. The manufacturing process of a medical-grade comfortable cotton-like fabric according to claim 1, characterized in that, The accelerator in step (1) is hexadecyltrimethylammonium bromide.

3. The manufacturing process of a medical-grade comfortable cotton-like fabric according to claim 1, characterized in that, The hydrogen content of the hydrogen-containing silicone oil in step (2) is 0.18% to 0.3%; the amount of the chloroplatinic acid catalyst is 10 to 20 ppm of the total mass of the reaction system.

4. The manufacturing process of a medical-grade comfortable cotton-like fabric according to claim 1, characterized in that, The mass ratio of hydrogen-containing silicone oil, allyl polyoxyethylene ether, methacryloyloxyethyl trimethylammonium chloride, and 3-(2,3-epoxypropoxy)propyltrimethoxysilane in step (2) is 100:25-35:8-12:4-6.

5. The manufacturing process of a medical-grade comfortable cotton-like fabric according to claim 1, characterized in that, The molecular weight of the allyl polyoxyethylene ether in step (2) is 400 to 600.

6. The manufacturing process of a medical-grade comfortable cotton-like fabric according to claim 1, characterized in that, The unblocking temperature of the blocked polyisocyanate crosslinking agent using methyl ethyl ketone oxime or ε-caprolactam as the blocking agent in step (3) is 130°C.

7. A medical-grade comfortable cotton-like fabric, applied to the preparation process of the medical-grade comfortable cotton-like fabric described in claims 1-6, characterized in that, The fabric has irregular micro-pits distributed on the fiber surface, and the micro-pits and fiber surface are anchored by chemical cross-linking of a terpolymer cross-linking network containing polyether segments, quaternary ammonium salt groups and epoxy groups.

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